summaryrefslogtreecommitdiff
path: root/fs/nfs/pnfs.c
diff options
context:
space:
mode:
authorBenny Halevy <bhalevy@panasas.com>2011-05-22 19:47:26 +0300
committerBoaz Harrosh <bharrosh@panasas.com>2011-05-29 20:52:32 +0300
commitfb3296eb4636763918edef2d22e45b85b15d4518 (patch)
tree31c85255ccfa03cbca2d1e4e52028e489276a73b /fs/nfs/pnfs.c
parentf7da7a129d57bfe0f74573dc03531c63e1360fae (diff)
pnfs: Use byte-range for layoutget
Add offset and count parameters to pnfs_update_layout and use them to get the layout in the pageio path. Order cache layout segments in the following order: * offset (ascending) * length (descending) * iomode (RW before READ) Test byte range against the layout segment in use in pnfs_{read,write}_pg_test so not to coalesce pages not using the same layout segment. [fix lseg ordering] [clean up pnfs_find_lseg lseg arg] [remove unnecessary FIXME] [fix ordering in pnfs_insert_layout] [clean up pnfs_insert_layout] Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Diffstat (limited to 'fs/nfs/pnfs.c')
-rw-r--r--fs/nfs/pnfs.c165
1 files changed, 126 insertions, 39 deletions
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index f57f5281a520..c2f09e9b670e 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -261,6 +261,65 @@ put_lseg(struct pnfs_layout_segment *lseg)
}
EXPORT_SYMBOL_GPL(put_lseg);
+static inline u64
+end_offset(u64 start, u64 len)
+{
+ u64 end;
+
+ end = start + len;
+ return end >= start ? end : NFS4_MAX_UINT64;
+}
+
+/* last octet in a range */
+static inline u64
+last_byte_offset(u64 start, u64 len)
+{
+ u64 end;
+
+ BUG_ON(!len);
+ end = start + len;
+ return end > start ? end - 1 : NFS4_MAX_UINT64;
+}
+
+/*
+ * is l2 fully contained in l1?
+ * start1 end1
+ * [----------------------------------)
+ * start2 end2
+ * [----------------)
+ */
+static inline int
+lo_seg_contained(struct pnfs_layout_range *l1,
+ struct pnfs_layout_range *l2)
+{
+ u64 start1 = l1->offset;
+ u64 end1 = end_offset(start1, l1->length);
+ u64 start2 = l2->offset;
+ u64 end2 = end_offset(start2, l2->length);
+
+ return (start1 <= start2) && (end1 >= end2);
+}
+
+/*
+ * is l1 and l2 intersecting?
+ * start1 end1
+ * [----------------------------------)
+ * start2 end2
+ * [----------------)
+ */
+static inline int
+lo_seg_intersecting(struct pnfs_layout_range *l1,
+ struct pnfs_layout_range *l2)
+{
+ u64 start1 = l1->offset;
+ u64 end1 = end_offset(start1, l1->length);
+ u64 start2 = l2->offset;
+ u64 end2 = end_offset(start2, l2->length);
+
+ return (end1 == NFS4_MAX_UINT64 || end1 > start2) &&
+ (end2 == NFS4_MAX_UINT64 || end2 > start1);
+}
+
static bool
should_free_lseg(u32 lseg_iomode, u32 recall_iomode)
{
@@ -467,7 +526,7 @@ pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
static struct pnfs_layout_segment *
send_layoutget(struct pnfs_layout_hdr *lo,
struct nfs_open_context *ctx,
- u32 iomode,
+ struct pnfs_layout_range *range,
gfp_t gfp_flags)
{
struct inode *ino = lo->plh_inode;
@@ -499,11 +558,11 @@ send_layoutget(struct pnfs_layout_hdr *lo,
goto out_err_free;
}
- lgp->args.minlength = NFS4_MAX_UINT64;
+ lgp->args.minlength = PAGE_CACHE_SIZE;
+ if (lgp->args.minlength > range->length)
+ lgp->args.minlength = range->length;
lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
- lgp->args.range.iomode = iomode;
- lgp->args.range.offset = 0;
- lgp->args.range.length = NFS4_MAX_UINT64;
+ lgp->args.range = *range;
lgp->args.type = server->pnfs_curr_ld->id;
lgp->args.inode = ino;
lgp->args.ctx = get_nfs_open_context(ctx);
@@ -518,7 +577,7 @@ send_layoutget(struct pnfs_layout_hdr *lo,
nfs4_proc_layoutget(lgp);
if (!lseg) {
/* remember that LAYOUTGET failed and suspend trying */
- set_bit(lo_fail_bit(iomode), &lo->plh_flags);
+ set_bit(lo_fail_bit(range->iomode), &lo->plh_flags);
}
/* free xdr pages */
@@ -625,10 +684,23 @@ bool pnfs_roc_drain(struct inode *ino, u32 *barrier)
* are seen first.
*/
static s64
-cmp_layout(u32 iomode1, u32 iomode2)
+cmp_layout(struct pnfs_layout_range *l1,
+ struct pnfs_layout_range *l2)
{
+ s64 d;
+
+ /* high offset > low offset */
+ d = l1->offset - l2->offset;
+ if (d)
+ return d;
+
+ /* short length > long length */
+ d = l2->length - l1->length;
+ if (d)
+ return d;
+
/* read > read/write */
- return (int)(iomode2 == IOMODE_READ) - (int)(iomode1 == IOMODE_READ);
+ return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
}
static void
@@ -636,13 +708,12 @@ pnfs_insert_layout(struct pnfs_layout_hdr *lo,
struct pnfs_layout_segment *lseg)
{
struct pnfs_layout_segment *lp;
- int found = 0;
dprintk("%s:Begin\n", __func__);
assert_spin_locked(&lo->plh_inode->i_lock);
list_for_each_entry(lp, &lo->plh_segs, pls_list) {
- if (cmp_layout(lp->pls_range.iomode, lseg->pls_range.iomode) > 0)
+ if (cmp_layout(&lseg->pls_range, &lp->pls_range) > 0)
continue;
list_add_tail(&lseg->pls_list, &lp->pls_list);
dprintk("%s: inserted lseg %p "
@@ -652,16 +723,14 @@ pnfs_insert_layout(struct pnfs_layout_hdr *lo,
lseg->pls_range.offset, lseg->pls_range.length,
lp, lp->pls_range.iomode, lp->pls_range.offset,
lp->pls_range.length);
- found = 1;
- break;
- }
- if (!found) {
- list_add_tail(&lseg->pls_list, &lo->plh_segs);
- dprintk("%s: inserted lseg %p "
- "iomode %d offset %llu length %llu at tail\n",
- __func__, lseg, lseg->pls_range.iomode,
- lseg->pls_range.offset, lseg->pls_range.length);
+ goto out;
}
+ list_add_tail(&lseg->pls_list, &lo->plh_segs);
+ dprintk("%s: inserted lseg %p "
+ "iomode %d offset %llu length %llu at tail\n",
+ __func__, lseg, lseg->pls_range.iomode,
+ lseg->pls_range.offset, lseg->pls_range.length);
+out:
get_layout_hdr(lo);
dprintk("%s:Return\n", __func__);
@@ -721,16 +790,28 @@ pnfs_find_alloc_layout(struct inode *ino, gfp_t gfp_flags)
* READ RW true
*/
static int
-is_matching_lseg(struct pnfs_layout_segment *lseg, u32 iomode)
+is_matching_lseg(struct pnfs_layout_range *ls_range,
+ struct pnfs_layout_range *range)
{
- return (iomode != IOMODE_RW || lseg->pls_range.iomode == IOMODE_RW);
+ struct pnfs_layout_range range1;
+
+ if ((range->iomode == IOMODE_RW &&
+ ls_range->iomode != IOMODE_RW) ||
+ !lo_seg_intersecting(ls_range, range))
+ return 0;
+
+ /* range1 covers only the first byte in the range */
+ range1 = *range;
+ range1.length = 1;
+ return lo_seg_contained(ls_range, &range1);
}
/*
* lookup range in layout
*/
static struct pnfs_layout_segment *
-pnfs_find_lseg(struct pnfs_layout_hdr *lo, u32 iomode)
+pnfs_find_lseg(struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_range *range)
{
struct pnfs_layout_segment *lseg, *ret = NULL;
@@ -739,11 +820,11 @@ pnfs_find_lseg(struct pnfs_layout_hdr *lo, u32 iomode)
assert_spin_locked(&lo->plh_inode->i_lock);
list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
- is_matching_lseg(lseg, iomode)) {
+ is_matching_lseg(&lseg->pls_range, range)) {
ret = get_lseg(lseg);
break;
}
- if (cmp_layout(iomode, lseg->pls_range.iomode) > 0)
+ if (cmp_layout(range, &lseg->pls_range) > 0)
break;
}
@@ -759,9 +840,16 @@ pnfs_find_lseg(struct pnfs_layout_hdr *lo, u32 iomode)
struct pnfs_layout_segment *
pnfs_update_layout(struct inode *ino,
struct nfs_open_context *ctx,
+ loff_t pos,
+ u64 count,
enum pnfs_iomode iomode,
gfp_t gfp_flags)
{
+ struct pnfs_layout_range arg = {
+ .iomode = iomode,
+ .offset = pos,
+ .length = count,
+ };
struct nfs_inode *nfsi = NFS_I(ino);
struct nfs_client *clp = NFS_SERVER(ino)->nfs_client;
struct pnfs_layout_hdr *lo;
@@ -789,7 +877,7 @@ pnfs_update_layout(struct inode *ino,
goto out_unlock;
/* Check to see if the layout for the given range already exists */
- lseg = pnfs_find_lseg(lo, iomode);
+ lseg = pnfs_find_lseg(lo, &arg);
if (lseg)
goto out_unlock;
@@ -811,7 +899,7 @@ pnfs_update_layout(struct inode *ino,
spin_unlock(&clp->cl_lock);
}
- lseg = send_layoutget(lo, ctx, iomode, gfp_flags);
+ lseg = send_layoutget(lo, ctx, &arg, gfp_flags);
if (!lseg && first) {
spin_lock(&clp->cl_lock);
list_del_init(&lo->plh_layouts);
@@ -838,17 +926,6 @@ pnfs_layout_process(struct nfs4_layoutget *lgp)
struct nfs_client *clp = NFS_SERVER(ino)->nfs_client;
int status = 0;
- /* Verify we got what we asked for.
- * Note that because the xdr parsing only accepts a single
- * element array, this can fail even if the server is behaving
- * correctly.
- */
- if (lgp->args.range.iomode > res->range.iomode ||
- res->range.offset != 0 ||
- res->range.length != NFS4_MAX_UINT64) {
- status = -EINVAL;
- goto out;
- }
/* Inject layout blob into I/O device driver */
lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
if (!lseg || IS_ERR(lseg)) {
@@ -903,9 +980,14 @@ static int pnfs_read_pg_test(struct nfs_pageio_descriptor *pgio,
/* This is first coelesce call for a series of nfs_pages */
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
prev->wb_context,
+ req_offset(req),
+ pgio->pg_count,
IOMODE_READ,
GFP_KERNEL);
- }
+ } else if (pgio->pg_lseg &&
+ req_offset(req) > end_offset(pgio->pg_lseg->pls_range.offset,
+ pgio->pg_lseg->pls_range.length))
+ return 0;
return NFS_SERVER(pgio->pg_inode)->pnfs_curr_ld->pg_test(pgio, prev, req);
}
@@ -926,9 +1008,14 @@ static int pnfs_write_pg_test(struct nfs_pageio_descriptor *pgio,
/* This is first coelesce call for a series of nfs_pages */
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
prev->wb_context,
+ req_offset(req),
+ pgio->pg_count,
IOMODE_RW,
GFP_NOFS);
- }
+ } else if (pgio->pg_lseg &&
+ req_offset(req) > end_offset(pgio->pg_lseg->pls_range.offset,
+ pgio->pg_lseg->pls_range.length))
+ return 0;
return NFS_SERVER(pgio->pg_inode)->pnfs_curr_ld->pg_test(pgio, prev, req);
}